The present invention relates to a switch lock-out device to prevent unintended operation of a power tool through inadvertent actuation of a trigger operably associated with a motor that operates the power tool.
Portable power tools (hedge trimmers, grass shearers and the like) as well as non-portable power tools (compound miter saws, radial arm saws and the like) include trigger mechanisms that have incorporated a lock-off feature, and in the case of some portable power tools, a lock-on feature, as well. The prior art contains many different types and kinds of lock-out devices, the construction and operation of which are shown in detail in the references supplied to the U.S. Patent and Trademark Office by applicants.
The present invention is directed to a switch lock-out device for power tools in which a trigger is mounted in a power tool hand grip and operates a switch actuator that is contained within the handle grip. In order to provide a switch lock-out feature for the trigger in this environment, the switch lock-out device must work in conjunction with the trigger that projects, in part, outside of the handle grip, as well as the switch actuator that is not accessible within the handle grip. At the same time, the switch lock-out device must prevent inadvertent actuation of the trigger which could result in unintended operation of the power tool.